In every surgery where intraoperative imaging is used it is a challenge to accurately perform the necessary steps of a procedure of treating a bone. Usually, almost each step requires an iterative process based on several X-ray images. A significant radiation exposure is thus produced. The amount of radiation may be highly dependent on the know-how and skill of the physician.
US 2008/0119728 A1 describes a system for video based registration between images during a skeletal medical procedure, the system includes a stereoscopic camera, a two dimensional image detector and a registration processor, the stereoscopic camera is associated with a stereoscopic coordinate system, the stereoscopic camera acquires a stereoscopic image pair of a fiducial mark, the fiducial mark is fixed onto a skeletal structure, a first fiducial representation of the fiducial mark is apparent on the stereoscopic image pair, the 2D image detector is associated with a 2D coordinate system and acquires at least two substantially different images of the skeletal structure, a second fiducial representation of the fiducial mark and a first skeletal representation of the skeletal structure is apparent on the two substantially different 2D images, the registration processor is coupled with the stereoscopic camera and with the 2D image detector and registers the stereoscopic coordinate system with a three dimensional (3D) coordinate system associated with a volumetric image detector, and superimposes 3D information on at least one volumetric image acquired by the volumetric image detector, according to the registration, the registration processor registers the stereoscopic coordinate system with the 3D coordinate system by registering the stereoscopic coordinate system with the 2D coordinate system using the first fiducial representation apparent in the stereoscopic image pair, and the second fiducial representation apparent in the two substantially different 2D images, and by registering the 2D coordinate system with the 3D coordinate system using the first skeletal representation apparent in the two substantially different 2D images, and the second skeletal representation apparent in the at least one volumetric image.